<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<title></title>
		<link rel="stylesheet" type="text/css" href="css/demo.css"/>
		<!--定义html的css规则-->
		<!--<style type="text/css">
			div{
				width: 300px;
				height: 200px;
				border: 1px solid red;
			}-->
		</style>
	</head>
	<body>
		<div id="">
			
		</div>
	</body>
</html>
